<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>CheckBox</title>
</head>
<body>
下面是一组复选框：
    <br>
    <input type="checkbox" name="a">
    <br>
    <input type="checkbox" name="a">
    <br>
    <input type="checkbox" name="a">
</body>
</html>